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Geochemical characteristics of Sr isotopes in the LS33 drill core from the Qiongdongnan Basin, South China Sea, and their response to the uplift of the Tibetan Plateau

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Acta Oceanologica Sinica 2023年第5期42卷 117-129页

作者： Ke Wang Shikui Zhai Zenghui Yu huaijing zhang College of Marine Geosciences Ocean University of ChinaQingdao 266100China Sinopec Matrix Co. Ltd.Qingdao 266000China Key Lab of Submarine Geosciences and Prospecting Techniques Ministry of EducationQingdao 266100China

Making full use of modern analytical and testing techniques to explore and establish new indexes or methods for extracting paleoseawater geochemical information from sediments will help to reconstruct the sedimentary paleoenvironment in different research *** connection between the subsidence of the South China Sea basin and the uplift of the Tibetan Plateau has been a scientific concern in recent *** explore the information on the sedimentary paleoenvironment,provenance changes and uplift of Tibetan Plateau contained in core sediments(debris),we selected core samples from Well LS33 in the Qiongdongnan Basin,South China Sea,and analyzed the contents of typical elements(Al,Th,and rare earth elements)that can indicate changes in provenance and the Sr isotopic compositions,which can reveal the geochemical characteristics of the paleoseawater depending on the type of material(authigenic carbonate and terrigenous detritus).The results show the following:(1)during the late Miocene,the Red River transported a large amount of detrital sediments from the ancient continental block(South China)to the Qiongdongnan Basin.(2)The authigenic carbonates accurately record changes in the 87Sr/86Sr ratios in the South China Sea since the *** ratios reflect the semi-closed marginal sea environment of the South China Sea(relative to the ocean)and the sedimentary paleoenvironment evolution process of the deep-water area of the Qiongdongnan Basin from continental to transitional and then to bathyal.(3)Since the Neogene,the variations in the 87Sr/86Sr ratio in the authigenic carbonates have been consistent with the variations in the uplift rate of the Tibetan Plateau and the sediment accumulation rate in the Qiongdongnan *** consistent changes indicate the complex geological process of the change in the rock weathering intensity and terrigenous Sr flux caused by changes in the uplift rate of the Tibetan Plateau,which influence the Sr isotope composition of s

关键词： sediments from a drill core grouping analysis elements and Sr isotopes provenance and paleoenvironment uplift of the Tibetan Plateau and subsidence of the South China Sea basin

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Heavy metals in suspended matters during a tidal cycle in the turbidity maximum around the Changjiang(Yangtze) Estuary

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Acta Oceanologica Sinica 2015年第10期34卷 36-45页

作者： zhang huaijing ZHAI Shikui zhang Aibin ZHOU Yonghua YU Zenghui College of Marine Geosciences Ocean University of China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of Education Qingdao Huanhai Marine Engineering Prospecting Institute

In order to discuss the content distributions and fluxes of heavy metals in suspended matters during a tidal cycle in the turbidity maximum around the Changjiang （Yangtze） Estuary, the contents of heavy metals （Zn, Pb, Cd, Co and Ni） have been analyzed. During a tidal cycle, the average contents of heavy metals are in the order of Zn〉Ni〉Pb〉Co〉〉Cd. The average contents in ebb tide are generally higher than that in flood tide. However, at the inshore Sta. 11, influenced by the contamination from the nearby waste treatment plant, the average contents of Zn and Ni in flood tide are higher than those in ebb fide and at the offshore Sta. 10, the content of Cd in flood tide higher than that in ebb tide due to marine-derived materials. The five heavy metals, mainly terrigenous, are transported towards east-northeast, and settle down with suspended matters in the area between Sta. 11 and Sta. 10. Influenced by marine-derived materials, the flux value of Cd does not alter significantly with obviously changing in flux direction towards northwest. The source of heavy metals, the salinity of water and the concentration of suspended matters are the main factors controlling the content distributions of heavy metals during a tidal cycle. There is a positive correlation between the contents of heavy metals （Zn, Pb, Co and Ni） and the salinity of water, while the opposite correlation between the contents and the concentrations of suspended matters. Because of marine-derived materials, the content of Cd is not correlated with the concentration of suspended matters and the salinity of water.

关键词： Changjiang (Yangtze) Estuary turbidity maximum zone tidal cycle suspended matters content ofheavy metal flux of heavy metal

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Heavy metals in Changjiang estuarine and offshore sediments:responding to human activities

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Acta Oceanologica Sinica 2012年第2期31卷 88-101页

作者： DONG Aiguo ZHAI Shikui Matthias Zabel YU Zenghui zhang huaijing LIU Feifei College of Marine Geoscience Ocean University of ChinaQingdao 266100China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationOcean University of ChinaQingdao 266100China Fachbereich Geowissenschaften Universitat BremenPostfach 330440D-28334 BremenGermany

The Changjiang （Yangtze） estuarine and offshore sediments were analyzed for total heavy metals concentrations and chemical fractions. Distributions of heavy metals show typical banded diffusion pattern, with high concentrations near the river mouth and following a decreasing trend in the offshore direction. According to chemical fractions, Fe/Mn oxide fraction is the major non-residual fraction in the Changjiang estuarine and offshore sediments, Higher percentage of non-residual fraction of Pb implies that, the industrial contaminations transported via the atmosphere and river input, may affect the non-residual fraction of heavy metals. Over past fifteen years, the concentration of Pb normalizing to A1 presents significant increasing trend, corresponding to the effect of human activities. By comparison of heavy metals fractions in 2003 to 2006, it has been realized that increasing water and sediment may cause a higher percentage non-residual fraction of Cu in the southern part of offshore muddy sediments.

关键词： sediment heavy metal fraction Changjiang (Yangtze) River

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Influence of Cathode Modification by Chitosan and Fe^(3+)on the Electrochemical Performance of Marine Sediment Microbial Fuel Cell

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Journal of Ocean University of China 2023年第3期22卷 709-716页

作者： ZAI Xuerong GUO Man HUANG Xiang zhang huaijing CHEN Yan JI Hongwei FU Yubin School of Materials Science&Engineering Ocean University of ChinaQingdao 266100China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China College of Marine Geosciences Ocean University of ChinaQingdao 266100China

The electrochemical performances of cathode play a key role in the marine sediment microbial fuel cells(MSMFCs)as a long lasting power source to drive instruments,especially when the dissolved oxygen concentration is very low in seawater.A CTS-Fe^(3+)modified cathode is prepared here by grafting chitosan(CTS)on a carbon fiber surface and then chelating Fe^(3+)through the coordination *** electrochemical performance in seawater and the output power of the assembled MSMFCs are both *** results show that the exchange current densities of CTS and the CTS-Fe^(3+)group are 5.5 and 6.2 times higher than that of the blank group,*** potential of the CTS-Fe^(3+)modified cathode increases by 138 *** output power of the fuel cell(613.0 mW m^(-2))assembled with CTS-Fe^(3+)is 54 times larger than that of the blank group(11.4 mW m^(-2))and the current output corresponding with the maximum power output also increases by 56 *** to the valence conversion between Fe^(3+)and Fe^(2+)on the modified cathode,the kinetic activity of the dissolved oxygen reduction is accelerated and the depolarization capability of the cathode is enhanced,resulting higher cell *** the basis of this study,the new cathode materials will be encouraged to design with the complex of iron ion in natural seawater as the catalysis for oxygen reduction to improve the cell power in deep sea.

关键词： marine sediments microbial fuel cell chitosan and iron chelation modified cathode electrochemical performance power output

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Humic Acid and Iron Chelation Modified Anode Improves the Electrochemical Performance of Marine Sediment Microbial Fuel Cell

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Journal of Ocean University of China 2022年第2期21卷 388-394页

作者： FU Yubin CHEN Jiaqi CHEN Yan HUANG Xiang LI Yang zhang huaijing ZAI Xuerong School of Materials Science and Technology Ocean University of ChinaQingdao 266100China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China College of Marine Geosciences Ocean University of ChinaQingdao 266100China

Marine sediment microbial fuel cell(MSMFCs)can be utilized as a long lasting power source to drive small instruments to work for long time on ocean floor and its higher power has a significant meaning for practical *** modification can greatly improve the performance of ***,humic acid(HA)and humic acid-iron ion complex(HA-Fe)were used to modify the anode for constructing a better *** results indicated that HA-Fe modified anode,better than HA modification,significantly improved the MSMFCs cell power *** maximum power density of HA-Fe modified MSMFCs is 165.3 mW m−2,which are 6.5-folds of blank *** number of microorganisms on anode,redox activity,and relative kinetic activity were 1.8-,6.1-,and 13.1-folds of blank MSMFCs,*** MSMFCs improvement would be attributed to the electron transfer media of HA and the valence conversion of Fe ions.A synergistic interaction between the naturally occurring HA and Fe ions on the anodic surface in marine sediments would make the modified anodes have‘renewable’characteristics,which is beneficial for the MSMFCs to maintain its long-term higher power.

关键词： marine sediment microbial fuel cells humic acid and iron complex modified anode electrochemical performance

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白云东矿高陡边坡滑体变形分析及治理对策研究

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金属矿山 2008年第5期37卷 20-23,116页

作者：张怀静北京科技大学北京建筑工程学院

结合白云鄂博铁矿东矿C区出现的边坡失稳问题,选取具有代表性的剖面,采用离散元软件UDEC对该边坡当前状态、按原计划开挖状态进行模拟计算及稳定性分析和评价,并且对模拟的结果进行了对比分析。同时根据现场情况及模拟结果,对C区边坡失... 详细信息

结合白云鄂博铁矿东矿C区出现的边坡失稳问题,选取具有代表性的剖面,采用离散元软件UDEC对该边坡当前状态、按原计划开挖状态进行模拟计算及稳定性分析和评价,并且对模拟的结果进行了对比分析。同时根据现场情况及模拟结果,对C区边坡失稳提出卸载及加固方案。

关键词：高陡边坡失稳离散元

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EXPERIMENTAL STUDY ON SEISMIC BEHAVIOR OF ENERGY-SAVING COMPOSITE CONCRETE SMALL-SIZED HOLLOW BLOCK WALL

EXPERIMENTAL STUDY ON SEISMIC BEHAVIOR OF ENERGY-SAVING COMP...

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The International Symposium on Innovation & Sustainability of Structures in Civil Engineering

作者： Weimin Sun huaijing zhang Hui zhang Xiaoluan Sun and Dachang zhang College of Civil Engineering Nanjing University of Technology Nanjing 210009 China

＜正＞Based on the cyclic reversed lateral loading tests of two pieces of energy-saving small-sized composite concrete hollow block masonry walls with window opening and two without window opening under constant vertical loading, the behavior such as failure mechanism, hysteretic characteristics, ductility, energy-dissipation capacity and stiffness degradation were studied. Simultaneously, the behavior of the cover layer under loading was discussed. What’s more, the effects of constructional measure and window opening on the seismic behavior of walls were studied. The test results showed that the composite concrete small-sized hollow block wall was not seriously damaged during loading, and outside cover layer can connect to the main bearing layer well and ensure it work together with main wall subjected to vertical and horizontal loading.

关键词： Energy-saving composite small-sized concrete hollow block masonry seismic behavior cyclic reversed loading test.

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地铁站换乘通道开挖对既有桩基的影响分析

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工业建筑 2009年第11期39卷 81-85页

作者：张怀静李维勋北京建筑工程学院北京100083 江西交通职业技术学院南昌330013

针对北京地铁10号线国贸桥地铁站换乘通道的设计和施工方案,采用有限差分数值模拟方法对不同方案下地铁车站换乘通道暗挖施工过程中上部既有桩基的受力特性及位移变化规律进行模拟,据以制定合理的施工方案。研究结果表明:在不对桥桩采... 详细信息

针对北京地铁10号线国贸桥地铁站换乘通道的设计和施工方案,采用有限差分数值模拟方法对不同方案下地铁车站换乘通道暗挖施工过程中上部既有桩基的受力特性及位移变化规律进行模拟,据以制定合理的施工方案。研究结果表明:在不对桥桩采取加固措施的情况下,地表沉降量和桥桩沉降量均较大,桥基承载力损失严重,严重影响到桥桩的稳定性。因此,在换乘通道开挖过程中,必须采取相应的工程加固措施来确保桥桩的稳定。

关键词：地铁换乘通道桩基数值模拟

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变截面连续梁动力特性的半解析解法

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北京科技大学学报 2008年第6期30卷 590-593,619页

作者：张怀静潘旦光北京科技大学土木与环境工程学院北京100083

基于Bernoulli-Euler梁理论,分析了多跨变截面连续梁的动力特性.应用模态摄动基本原理,利用等截面连续梁的模态,将变截面连续梁微分方程的求解转化为代数方程组求解.该方法对于梁的截面函数的连续性要求较少,既适用于截面变化为阶跃形... 详细信息

基于Bernoulli-Euler梁理论,分析了多跨变截面连续梁的动力特性.应用模态摄动基本原理,利用等截面连续梁的模态,将变截面连续梁微分方程的求解转化为代数方程组求解.该方法对于梁的截面函数的连续性要求较少,既适用于截面变化为阶跃形式的梁,也适用于截面函数连续的梁.通过算例分析表明,这一方法可有效地简化计算,同时计算结果具有较高的精度.

关键词：变截面连续梁动力特性半解析解模态摄动法

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不同代PAMAM树状大分子与牛血清白蛋白的相互作用研究

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化学学报 2010年第17期68卷 1741-1748页

作者：张怀敬何华李杉杉芦金荣 Chuong Pham-Huy 中国药科大学分析化学教研室药物质量与安全预警教育部重点实验室中国药科大学有机化学教研室 Faculty of Pharmacy University of Paris V4 avenue de l’Observatoire75006

采用发散法合成了以乙二胺为核的聚酰胺-胺型(PAMAM)树状大分子,并应用荧光光谱法研究了生理条件下(pH=7.4)3.0代(G3.0)、3.5代(G3.5)和4.0代(G4.0)PAMAM树状大分子与牛血清白蛋白(BSA)的相互作用.结果表明,三种PAMAM树状大分子都能引... 详细信息

采用发散法合成了以乙二胺为核的聚酰胺-胺型(PAMAM)树状大分子,并应用荧光光谱法研究了生理条件下(pH=7.4)3.0代(G3.0)、3.5代(G3.5)和4.0代(G4.0)PAMAM树状大分子与牛血清白蛋白(BSA)的相互作用.结果表明,三种PAMAM树状大分子都能引起牛血清白蛋白荧光猝灭,其程度主要取决于各自末端基团的性质,猝灭机制属于静态猝灭.G4.0PAMAM,G3.5PAMAM和G3.0PAMAM与BSA的猝灭常数分别为2.73,1.69,1.55L·mmol-1.同时考察了体系pH值及离子强度的变化对PAMAM与BSA相互作用的影响.此外,同步荧光和紫外光谱法(UV)以及红边激发荧光位移(REES)等方法的研究结果表明,PAMAM树状大分子的存在改变了BSA的构象.

关键词： PAMAM树状大分子牛血清白蛋白荧光猝灭同步荧光光谱红边激发荧光位移

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